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Sunday, February 10, 2008

Potholes

My husband is concerned (again) about my sanity because I have developed a (hopefully temporary) obsession with POTHOLES. How could I not? Living in Waterloo, Ontario - allegedly The World's Top Intelligent Community 2007 - it is hard to get around them. Just look at this crap (crap referring to the quality of the video as well as that of the street)

I took this video yesterday. This street was newly paved 2 months ago. Here some photos (click to enlarge):

I've come to appreciate if there is snow on the ground, because it does at least fill these holes! Thaw is especially bad, because it's hard to tell the depth of a hole filled with water. And that bad shape of the pavement is not a problem confined to the cities. The last time I was courageous enough to take the highway 401 to Toronto, the road condition was worse than that of every highway I've taken in southern Africa, including the Trans-Kalahari highway. (The traffic on the 401 was considerably higher though.) Folks, I usually don't like to let my European genes enter my argumentation [1], but I've never, ever seen the streets in a Germany city in such a pity state.

And now don't give me that crap with the harsh climate. This winter has been very mild here this year, and I've seen winters in Germany where the temperature did drop to a - 20 °C as well.

I've had the Your-Streets-Suck argument previously in various places in the USA. Depending on the state, the excuse then is 'Yeah, but here it gets much warmer than in Germany'. Or, 'Yeah, but we have much heavier rainfalls than in France'. And if it's not that, then the ground is extraordinarily difficult to deal with or the vegetation causes problems, or maybe the potholes are on purpose just to keep the German tourists off speeding on the highways. Okay, I've been driving 240 km/h on the Autobahn, but admittedly I know about nothing about paving a street. Let me instead show you some pictures so you know what I mean.

Types of Damage

The one kind of damage that is caused by frost are lengthwise cracks which look like this (photos probably taken in Austria)

This kind of crack is caused if the water in the ground below the pavement freezes, expands, and pushes up the asphalt. It will typically crack in the middle where the elevation is the highest [2]. The other kind of cracks I have seen often are net cracks which look like this:

And these are caused when the frozen water thaws in the ground under the pavement, can not flow off to the sides, but can only escape to the top through the asphalt. Which, under pressure, causes a net of cracks.And then of course there are potholes. Some of them can get bad, some get really bad and grow to Waterloonian size, but the ones I remember from my days in Germany most often look somewhat like the pic to the right (photo: Hessische Straßen und Verkehrsverwaltung). What you see there is a hole in the top layer, probably a result of one of the above mentioned net cracks.

Groundbreaking!

Now these mentioned kind of cracks I've seen occurring here as well, but the additional problem is that here these defects seem to grow, and they grow rather rapidly. If water can collect below the pavement in a loose ground, thaw will leave the street surface all brittle and an ideal candidate for huge holes. These defects grow further because once the upper layer has a defect the ground below is mostly loose shoulder. Cars driving through the holes loosen more of the ground which shifts, and the rims of the hole increase, while it also gets deeper. On a busy street it doesn't take long for a crack to grow to a size that will at least ruin your wheel alignment, if not your tires (not to mention the lacquer). And do you know what they do with these holes? They fill them with gravel - a procedure I've seen the first time in Botswana, just that there were usually much faster with that first aid maintenance.

Though I admit that Waterloo can't quite keep up with Detroit, look at this.

To the left is an example, (photo taken here in Waterloo this morning), of how one of these lengthwise cracks develop with a bad underground (larger version). You find these holes in abundance on Weber street towards North. It's hard to tell but it looks to me the newer the pavement, the faster the pothole growth.

Bad underground is especially problematic on highways. If there is constant heavy traffic on the street, unfortified ground tends to shift under pressure which causes lane grooves that are esp. dangerous during rain. Not to mention that it promotes the pothole growth.

Why am I telling you that?

A) Because it pisses me off. There are plenty of reasons to leave Germany. My top three list is: the GEZ, the shop opening hours, and BMW drivers. But at least they know how to pave their streets.

B) Because it gives you an example for system failure. I can see two reasons for that crap (Pfusch am Bau).

1) One is that a better quality would be more expensive than fixing the road frequently, and providing constant maintenance service during the winters. It could be more expensive because the technique is likely more effort, but it gets increasigly difficult if the machinery/people/expertise is not easily available. That price argument fails to take into account damage caused by these street conditions, cost that has to be carried by drivers. Not to mention that annoyance doesn't have an immediate monetary equivalent. It could also be that the maintenance service runs on different budget (state/city), so doesn't weigh in at the right place.

2) Second, if that is not the case it could just be they pleasantly ignore there is a huge scope for improvement. Sounds somewhat odd, but look at this video (somewhere Milwaukee) or this video (Boston), in neither of which anybody even attempts to ask whether these bad conditions could be, to some degree, avoidable. Scary in a different way is this video from Montreal where the speaker explains the washed away ground is due to leaking pipes, but I agree with his conclusion to stop the cosmetics and rebuild the roads completely.

Bottomline

If you ask me the most intelligent community of the world should get itself some pavement engineers, pronto. Who needs theoretical physicists?

See also: Berkeley's Pavement Research Center.[1] The easiest way to annoy an American citizen is to challenge his or her national pride. He will either label you anti-American and therby justify his right to dismiss everything the arrogant Europoean says (because she's of course just jealous her passport has the wrong color). Or the discussion will inevitably approach the big attractor Hitler. And yes, restrictions apply. As always. And you are the one exception.

[2] It is of a certain advantage if the street elevation is the highest in the middle so the water can flow off to the sides. I am mentioning this because typically in Tucson I recall the center of the crossings are the lowest points. Which is great because if it rains, water can stay there half a meter deep. The city is therefore covered with 'do not enter when flooded' signs that you should take really seriously. But hey, that's just because they have so heavy rainfalls.

38 comments:

On my way back from Saarland this afternoon, I've seen these very characteristic patterns of "Schadensbild Frostschaden" and "Schadensbild Tauschaden" on nearly each one of the smaller roads - but at least, there are no potholes!

“The French brigade of cuirassiers guarding d'Erlon's left flank were still dispersed, and so were swept over the deeply sunken main road and then routed.[58] The sunken lane acted as a trap which funnelled the flight of the French horsemen to their own right, away from the British cavalry. Some of the cuirassiers then found themselves hemmed in by the steep sides of the sunken lane”

I am not an American, and I do not like the American way of life, and I have avoided going there as much as possible. Having said that, I have to admit that there is such a thing as vicious anti-Americanism, that it is extremely widespread, and that Americans can be excused for suspecting its presence when they hear their country criticised. Which they do. A lot. Especially by students from China and India, who hate the US so much that, at the end of their studies, they fight desperately to be allowed to stay on in that terrible place for an indefinite period. As for playing the Hitler card: that is playing dirty. Still, one has to admit that the spirit of fanatical self-righeousness that one encounters sometimes among young Germans, especially about environmental issues, can be pretty scary.

Europe can learn as much from America as the other way round. Think about the EU - the USA have a lot experiences with the problems that European Union still has to face. Regarding environmental issues: it is pretty damn hard not to point out every one and then that the suddenly emerging American green-ness is lagging behind some decades. I mean, to give you an example I just came across: Canada has discovered the No-Junk-Mail sticker! Yes, it saves a lot of paper waste! Congratulations! My parents have had one since the early 90ies or so. Maybe there will be a point when they do indeed introduce bottles that can be returned and reused. That has nothing to do with self-righteousness, it is more a plea to everybody in this world to not just stare at their own navel. Best,

Anyway, Bee, have you considered that perhaps the condition of the roads has more to do with how the contracts to build the roads are awarded, and has very little to do with the engineering of road building?

I live in Washington State, which has the same weather as British Columbia, and we have way fewer problems with potholes than any of the eastern states I used to live in. Yes, we have snow and ice, and the temperature gets cold, but the weather is much harsher back east, and they get lots more potholes.

It's not just the cold and how deeply the ground freezes. The frequency of snow plowing doesn't help, because snow plows weaken the surface. There is a seasonal road through the Cascades here that is closed in the winter, and it still has the original 1930s surface.

I gather that there has been some more work on paving technology in the EU, but there are harsher conditions in some parts of the world.

P.S. New York City used to have a terrible time with its potholes. Then, they passed a law allowing drivers to collect damages for their car if it was caused by a pothole that the city was aware of. A group of lawyers set up a reporting group to notify the city whenever they found a pothole. After this, the city got much better at fixing potholes.

You may be interested to read this as it relates to the difference between Ontario’s 400 series series highway road beds and what’s typically done in the U.S. As can be seen there is some controversy. In my experience we started to get a lot more potholes when they went to what I refer to as the peel and stick practice in road resurfacing. That’s where they chew off a few inches of asphalt and then pave a couple of inches back on. I’ve noticed these surfaces start falling apart as soon as the first year. I believe there is a flaw as far as the adhesion goes with this technology.

Hello Bee,I visited a then rather new research site of a big company in Pittsburg in the 80ties.On the streets there, I saw a structure like the "Netzrisse", but without any cracks. It was very regular, most hexagons and nearby-hexagons. The structure was made from grey lines, I could not see cracks. When I asked, they answered this is common in the area, reason behind was the big differences in winter to summer temperatures. The process, so they said, would lead to cracks within some years.Mudcracks, developed when mud dries, often look similar. And here is where theoreticians come in:they could find "Reason" for the structures, why do they look as they look?Potholes are much less annoying, when You know. :=)On the steets of a chemical site in Wiesbaden (Germany) in 1980 I saw a lot of rather shallow potholes whereas the streets in general were very well kept, some of them brandnew. Of course I asked for the reason. The potholes were caused by some of the materials produced there: cellulose ethers like methyl- , hydroxyethyl and so on.If You ever glued wallpaper: this is done with methyl cellulose or carboxymethyl cellulose When a small amount of certain qualities was spilled on the street and was wetted by rain, a patch of a slimy film developed. On drying, this filmshrunk and tore the upper layer of the asphalt out of the street. RegardsGeorg

I hope the horrible environmental polution described in the previous post has been ameliorated since then.

I agree that the state of the potholes is largely a function of the government's desire to provide decent streets. There's no secret technology involved. There are Roman roads still usable in very frosty regions.

Have you considered that it might not be in the interest of the construction company that does the road repairs to build the perfect road that never breaks?

That might be quite an important factor especially since the public/private business in construction work is known to be particularly prone to corruption. Not to mention organised crime which is in some pars of the US dominating the construction industry (as I was explained).

Another aspect might be that roads constructed at freezing temperatures might have intrinsic problems once the water contained in the tarmac melts again.

Thanks for the link! Given that the article is 7 years old already it is really depressing to see the absence of any change.

Dear Arun:

have you considered that perhaps the condition of the roads has more to do with how the contracts to build the roads are awarded, and has very little to do with the engineering of road building?

Yes. That's why I called it a system failure. Americans being what Americans are, I have no doubt they could do it if they really wanted to.

Hi Kaleberg:

It's not just the cold and how deeply the ground freezes. The frequency of snow plowing doesn't help, because snow plows weaken the surface.

Yes, sorry, I read that somewhere but forgot to mention it, thanks for reminding me! Also, the overuse of salt makes the situation worse, because it allows much more water to sink into the pavement than would usually be the case.

Hi Robert:

Have you considered that it might not be in the interest of the construction company that does the road repairs to build the perfect road that never breaks?

I considered that as well, but I would not locate the cause of the problem there. It is clearly possible to build roads of much better quality and everybody who is in the business probably knows that. If a state hires a crappy service they probably know it is crap and doesn't solve the problem. So I guess they either do so to save money in the wrong places, or because there isn't sufficient supply of companies that can provide high quality pavement.

I guess it is a combination of both. It seems to go nicely with the philosophy that I've encountered repeatedly (and that still drives me nuts): why do it right, if you can do it sloppy and just fix it every two months (the streets, the plumbing, the roof, the air condition, the heating...).

Since we already had the 'green consciousness' on the table, I hope that rather sooner or later somebody will come to realize that constantly replacing or fixing things is an incredible waste of energy.

If you don't want your adhered aggregate to catastrophically fragment you add fiber. This is true for concrete, asphalt, and piece of crap Space Scuttle foam. It would be idiot simple and cheap to add geotex, glass/rock wool, etc to asphalt during emplacement and double or triple its mean time to failure.

Uncle Al contacted NASA about insulating the Space Scuttle in the high tech sustainable manner of a hot tub or water heater. Apparently trying to keep the heat out rather than in would require blowing the foam inside-out, 0.1% added carbon fiber notwithstanding.

The worst roads I have encountered were in Romania ... on a 'shortcut' where the highest possible average speed was about 10km/h. The fraction of pothole to road was approaching 0.5.

After that comes Greece, I guess, particularly Crete, then parts of Detroit. But Heidelberg is pretty awful too. The main road south from HD was built in cobblestones many decades agohttp://ww2.heidelberg.de/stadtblatt-online/index.php?artikel_id=2338then covered with a few inches of tarmac, which every few years has tended to decay in patches or break down completely. So there are a few hundred metres where you have to drive on the stones...

The easiest way to annoy an European citizen is to challenge his or her national pride. He will either label you anti-European and therby justify his right to dismiss everything the arrogant American says (because she's of course just jealous her passport has the wrong color). Or the discussion will inevitably approach the big attractor Bush. And yes, restrictions apply. As always. And you are the one exception.

Potholes happen because most asphalts contain paraffins. When the weather gets cold, the paraffins crystallize and the asphalt loses its structural cohesiveness, basically it crumbles to pieces - that's why whole chunks are missing.

Different asphalts contain different amounts of paraffins, and I suspect different paraffins have different crystallization temperatures. Heavy traffic (trucks) of course make the problem worse. SUV's are secondary, since they are still much smaller than trucks (and, more importantly, their tire pressures aren't much higher than those of car tires).

I guess the road builders in Ontario must have used a high-paraffin asphalt for their latest projects. When I was there, there were lots of cracks, but I don't remember potholes as much.

If that challenge was aimed at me however you've completely missed the target. I am not proud to be German. National pride isn't a concept that resonates with me. I don't understand how I should be proud of something I had nothing to do with. I didn't ask to be born, and I certainly didn't specify the coordinates.

On a global scale, compared to most of the world population, I think though I was very lucky to be born in Germany. On that same scale however, it doesn't make a big difference whether my passport is blue or red.

It is kind of interesting how these patters repeat on different levels: Frankfurt, where I was born, has a counterpart on the other side of the river (Offenbach). People from both sides like to mock each other about this (Hibbedebach, Dribbedebach). If you put the Hessians together with Bavarians though, the Hessians will likely drop their local differences and make fun of the Bavarians, and the Bavarians will make fun of the Hessians. Put Germans together with Italians, and you see the same kind of mockery on a national level. It is quite interesting sometimes to follow this kind of in- and outgroup behavior attached to social and cultural identity.

Hi Bee - this warm/wet/cold winter hasn't helped but I think a lot has to do with the dreadful way they pave now, something not likely to get better given that asphalt is made from that well known commodity fetching $95/bbl.

Hi Bee,do you remember when we visited the new eastern "Bundeslaender" in 1990 there were a lot of traffic signs 80-60-40, which mean: in a distance of 80m are 60 potholes which are not been repaired for 40 years!Best Mum

Sadly both your post and my 'challenge' (a strange reading of 'however') are both relatively true. I personally find the ugly American more annoying but that may be because of my United States passport. Nationalism is so 20th century.

Bee - You came up in converstation today! At the deli today (after snowboarding of course!) the owner and another custy were discussing how pavement put down this past fall over a small bridge was already chewed up. "Oh you should hear whats going on in Waterloo...its so bad a woman I know has started videoing the carnage and putting it online.." I think I gave them an idea!

This is interesting. Do you think it is likely there will be some innovation that helps dealing with the problem?

My limited understanding is that only solution is to use asphalts that contain no paraffins. My dad says asphalts from Venezuela and Romania are low in paraffins and hence make good (but expensive) roads, whereas Russian asphalts crumble in the winter (those had been used on roads in Slovakia and we had our share of potholes after every winter).

On the other hand, many internet sites suggest that potholes are caused be freezing and thawing of water that seeps between the pavement layers, so maybe I was wrong all along.

Hello Lafo,"On the other hand, many internet sites suggest that potholes are caused be freezing and thawing of water that seeps between the pavement layers, so maybe I was wrong all along."Right. As You wrote, this goes back to some Slowakian/Russian experience, in the west, this is impossible since 50 years at least. First: "paraffin" does not exist, this is the name of a category of organic compunds. I think You refer to "paraffin wax",this could do such harm. "Asphalt" is made from the "vacuum residue" in oil refinerys. Paraffin wax (along with all the other more volatile fractions) is distilled off almost competely and sold as paraffin wax "mostly for candles).The residue is treated afterwards by blowing with air for about 3 days at about 300° C.This process oxidizes anything oxidizable and blows out any traces of volatiles. By variation of time/temperature in this step different types of bitumen (laymens "asphalt") are made.Not all crudes can be processed in this way, if not, the vacuum residue is burned as a feed for steam boilers.RegardsGeorg

many internet sites suggest that potholes are caused be freezing and thawing of water that seeps between the pavement layers,

That is also what the file said that I linked to above. Unfortunately, I just noticed that the link doesn't work. It was in German anyway, so probably not of much help. It summarized the results of a durability study on asphalt depending on whether or not some kind of 'glue' was used to avoid different layers can shift against each other. As one can guess it turns out the durability increases noticable if the layers are well bonded. Best,

Read Snowcrash. While I found the primordial language angle very interesting I thought his prose skills failed during the second half. He did have an ending. While I may be more interested in en.wikipedia.org/wiki/The_Dispossessed I fear en.wikipedia.org/wiki/The_Sheep_Look_Up may be more plausible at this point.

I found the concept of nations being replaced by global companies interesting and actually plausible. Though it is to me of some concern. What I would like to see instead are 'nations' as political systems become 'global', i.e. disentangled from their local attachment (the local politics is a not necessarily directly related aspect). I am thinking of a generalized 'social contract'. I recently found that Ulrich Beck (English version), a very interesting German sociologist, also argues to balance transnational companies by 'Transnational states'.

And of course I've read the Dispossessed... it seems to be one of the little not-negative political utopias that were written at this time.

I was surfing the net on potholes. Where I live, Rockford, Il. a city 90 miles (145 km) northeast of Chicago, I have never seen potholes as bad here in my entire life! It is a pet peeve of mine also.

I am not a civil engineer but the following I think are common sense reasons why we have such pothole problems.

1. Temperature extremes. (This hasn't ever changed)

2. Salting the living hell out of the roads in the winter and not using less damaging mechanical snow removal methods.

3. Using the lowest bidder for road projects along with politics that leads to lousy contractors. Along with this is overlooking quality and longevity of the contractor's work and materials used over initial price.

4. Roads that are not built with enough grade (slope) to facilitate water run off, thereby reducing the damage of freeze thaw. Roads decades ago had much more grade than now.

5. Dramatic reduction in road funding due to spending in other areas, namely the military complex and not keeping our damn noses out of other countries business. Examples: Korea, Vietnam, and oh yes, Iraq. Can you say 12 billion dollars a month! That's what America is pissing away every month in Iraq.

6. Lawyers (here in America)

I recently was in Frankfurt and Paris and noticed roads much better there.